Volume containers polypropylene

A The extraction of additive concentrates. These are mixed additive packages (which may also contain polypropylene) containing up to six additives at individual levels of typically 2-20%. They do not need an exhaustive extraction procedure but do require a sampling technique that ensures a representative sample, and in some cases a dilution step will be necessary. The extraction procedure generally used is a direct extraction with a fixed volume of solvent at ambient temperature using an ultrasonic bath. Extraction periods of up to 30 min are used. The solvents generally used are carbon tetrachloride for IR measurements, 1,2-dichloroethane for non-aqueous potentiometric measurements, and chloroform with subsequent dilution with excess methanol for HPLC measurements [16]. 

For dealing with smaller volumes of solution, micropipettes, often referred to as syringe pipettes, are employed. These can be of a push-button type, in which the syringe is operated by pressing a button on the top of the pipette the plunger travels between two fixed stops and so a remarkably constant volume of liquid is delivered. Such pipettes are fitted with disposable plastic tips (usually of polythene or polypropylene) which are not wetted by aqueous solutions, thus helping to ensure constancy of the volume of liquid delivered. The liquid is contained entirely within the plastic tip and so, by replacing the tip, the same pipette can be employed for different solutions. Such pipettes are available to deliver volumes of 1 to 1000 pL, and the delivery is reproducible to within about 1 per cent. 

Ny lon-6 (108 g) carpet backed with calcium-carbonate-filled latex and polypropylene was charged to a 1000-mL three-neck round-bottom flask (equipped with a condenser) with 6 mL of 85% phosphoric acid. Superheated steam was injected continuously during a 45-min period. The vapor temperature of the reaction medium was 250-300°C. The volume of distillate collected was 1065 mL. The distillate contained 1.9% e-caprolactam (as determined by GC), which corresponded to a crude yield of 37.5%. The distillate was fractionated in a distillation column and the nonaqueous phase removed. The remaining aqueous phase was treated with 2% potassium permanganate at 40-50°C for 2 h. Evaporation of... 

Standards, controls, and samples (250 fiL each) were treated with 500 fiL acetonitrile-acetic acid (99 1 v/v) containing IS (2.50 jUg/mL), vortexed for 10 sec, incubated for 5 min, and centrifuged at 15,000 g for 5 min. The supernatants (1650 //L) were loaded onto a polypropylene 96-well plate containing 900 fxL HPLC water under low vacuum. The SPE plates were conditioned with 500 fxL methanol followed by 300 jx. acetonitrile-water-acetic acid (30 69.5 0.5 v/v/v) (solvent A), washed with 1000 /xL solvent A, dried under full vacuum for 10 min, wiped dry with paper, eluted with 500 jxL methanol-trifluoroacetic acid (99.9 0.1 v/v) (solvent B) and then with 400 //L solvent B for 2 min, evaporated to dryness at 65°C under a gentle air stream, reconstituted with 200 /xL methanol-hydrochloric acid (0.1 M) (70 30 v/v) and assayed. The injection volume was 50 i L. Figure 11.3 shows chromatograms of blank plasma and spiked plasma with lumefantrine. A calibration curve was constructed in a concentration range of 25 to 20,000 ng/mL. Intra-assay and interassay coefficients of variation were below 5.2 and 4.0%, respectively. The limit of detection was 10 ng/mL. The limit of quantification was 25 ng/mL. 

A standard stock solution of sirolimus was prepared in methanol. Controls and standard working solutions were prepared by spiking blank whole blood with the stock solution. Standards, controls, and patient whole blood (10 fi. ) were transferred to 1.5 mL polypropylene tubes, mixed with 40 fiL of 0.1M zinc sulfate solution, precipitated with 100 fiL of methanol containing the IS (2 fig/L), vor-texed vigorously for 5 sec, and centrifuged at 10,500 g for 5 min. Supernatants were collected and assayed. The injection volume was 20 fiL. The retention times of sirolimus and ascomycin were 0.93 and 0.89 min, respectively. The total run time was 2.5 min. Representative MRM chromatograms of a patient sample are shown in Figure 11.6. 

In an effort to optimize the solvent-containing passive sampler design, Zabik (1988) and Huckins (1988) evaluated the organic contaminant permeability and solvent compatibility of several candidate nonporous polymeric membranes (Huckins et al., 2002a). The membranes included LDPE, polypropylene (PP), polyvinyl chloride, polyacetate, and silicone, specifically medical grade silicone (silastic). Solvents used were hexane, ethyl acetate, dichloromethane, isooctane, etc. With the exception of silastic, membranes were <120- um thick. Because silicone has the greatest free volume of all the nonporous polymers, thicker membranes were used. Although there are a number of definitions of polymer free volume based on various mathematical treatments of the diffusion process, free volume can be viewed as the free space within the polymer matrix available for solute diffusion. 

Antec 95. Volume I. Conference proceedings. Boston.Ma., 7th-llth May 1995, p.406-10. 012 MICROCELLULAR FOAMING OF POLYPROPYLENE CONTAINING LOW GLASS TRANSITION RUBBER PARTICLES IN AN INJECTION MOULDING PROCESS Wang C Cox K Campbell G A Clarkson University (SPE)... 

Thermoplastic Polymers. Most thermoplastic polymers are used in high-volume, widely recognized applications, so they are often referred to as commodity plastics. (We will elaborate upon the distinction between a polymer and a plastic in Chapter 7, but for now we simply note that a plastic is a polymer that contains other additives and is usually identified by a variety of commercial trade names. There are numerous databases, both in books [1] and on the Internet [2], that can be used to identify the primary polymer components of most plastics. With a few notable exceptions, we will refer to most polymers by their generic chemical name.) The most common commodity thermoplastics are polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC) and polystyrene (PS). These thermoplastics all have in common the general repeat unit -(CHX-CH2)-, where -X is -H for PE, -CH3 for PP, -Cl for PVC, and a benzene ring for PS. When we discuss polymerization reactions in Chapter 3, we will see that all of these thermoplastics can be produced by the same type of reaction. 

Micropipets (Figure 2-12) deliver volumes of 1 to l 000 jxL (1 jjlL = 10-6 L). Liquid is contained in the disposable polypropylene tip, which is stable to most aqueous solutions and many organic solvents except chloroform (CHC13). The tip is not resistant to concentrated nitric or sulfuric acids. To prevent aerosols from entering the pipet shaft, tips are available with polyethylene filters. Aerosols can corrode mechanical parts of the pipet or crosscontaminate biological experiments. 

A two mL capacity polypropylene container with sealable screw-top lid and V shaped bottom. Ideal for storing dried organisms (e.g., amphipods) and water samples and good for digesting small tissue samples because small acid volumes remain in contact with tissue samples. Volume 1(12). 

Withdraw the hemolymph from one to several hundred individuals in order to get a sample volume of at least 0.1-100 pL in prechilled polypropylene tubes containing an anticoagulant buffer supplemented with PTU (1 pg/mL) and a protease inhibitor (e.g., aprotinin at a final concentration of 40 pg/mL PMSF is also an alternative). 

Diazepam Diazepam should not be administered with some plastics/PVC/ volume control chambers of cellulose proprionate. Administered sets containing glass, polyolefin, polypropylene, and polyethylene may be used for such infusions. Diazepam is incompatible with many drugs, hence it should not be mixed with infusions containing other drugs.155156... 

The pipettes are all based on air displacement with a simple plunger and are provided with non-wettable plastic (usually polypropylene) disposable tips to contain the solution, preventing any contamination of the pipette itself. Most micropipettes have a double action plunger system, i.e. calibration and overshoot positions, which ensures that the sample is completely dispensed. There are many manufacturers offering a complete range of volumes in addition some have available a selection of pipettes with adjustable volumes. 

A large-volume intraocular solution (for irrigation) may be packaged in a polyolefin (polyethylene and/or polypropylene) container. 

The enzymatic reaction was carried out in 1.5 mL polypropylene centrifuge tubes containing in a total volume of 250 /nL 125 /nmol 3-/V-morpholinopro-panesulfonate buffer (pH 7.5), 1.25 of /nmol glutathione, xenobiotic substrate (1.25 /nmol of iodomethane, 1.25 /nmol of iodoethane, 0.12 /nmol of methyl parathion, or 1.25 of /nmol dichlorvos), and enzyme. Reactions were initiated by adding the xenobiotic substrate dissolved in 5 /nL of ethanol and terminated after incubation at 30°C by adding 25 /nL of ice-cold 60% perchloric acid. 

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